System apparatus and method for extracting electronic-grade chemicals from coal tar wash oil fractions

Abstract

This invention relates to a system apparatus and method for extracting electronic-grade chemicals from coal tar wash oil fractions, comprising: a pretreatment unit, a mixed methylnaphthalene refining unit, a fluorene refining unit, and an acenaphthene refining unit; the side-stream outlet of the pretreatment unit is connected to the inlet of the mixed methylnaphthalene refining unit; the bottom outlet of the pretreatment unit is connected to the inlet of the fluorene refining unit; and the bottom outlet of the fluorene refining unit is connected to the inlet of the acenaphthene refining unit. The system apparatus provided by this invention, through the selection and design of the equipment within the system, achieves the extraction of electronic-grade chemicals from coal tar wash oil fractions, particularly targeting isomer systems within the target components. After effective initial separation, subsequent distillation separation and purification are performed, ultimately achieving the extraction of electronic-grade chemicals.

Description

Technical Field

[0001] This invention relates to the field of chemical technology, and specifically to a system apparatus and method for extracting electronic-grade chemicals from coal tar wash oil fractions. Background Technology

[0002] Currently, coal tar wash oil fractions (200-330℃) contain a large amount of valuable polycyclic aromatic hydrocarbons (PAHs) such as β-methylnaphthalene, α-methylnaphthalene, acenaphthene, fluorene, and fluorene. These PAHs can be chemically synthesized to obtain polycyclic aromatic hydrocarbon derivatives. These derivatives have excellent electrical conductivity and can be excited by light or electric fields to produce strong fluorescence, making them suitable as monomer raw materials for organic electroluminescent devices. These polycyclic aromatic hydrocarbon derivatives also have excellent properties such as high thermal stability, low dielectric constant, and low dielectric loss. They can be used as carbon matrix, high-temperature resistant and ablation-resistant materials in the fields of biosensors and aerospace materials, and as special resin materials in the field of 5G copper clad laminates.

[0003] Currently, the separation and purification of polycyclic aromatic hydrocarbons such as β-methylnaphthalene, α-methylnaphthalene, acenaphthene, fluorene, and fluorene in domestic coal tar mainly rely on processes such as distillation separation, solvent crystallization, melt crystallization, and distillation-recrystallization. The principle of these processes is to achieve separation and purification by utilizing the difference in melting point or boiling point of the substances.

[0004] For example, CN101982523A discloses a continuous processing method for washing oil, which uses negative pressure distillation to finally obtain industrial acenaphthene, industrial fluorene and industrial fluorene products with a purity of ≥95%.

[0005] CN112933633A discloses a method for continuous negative pressure distillation separation and refining of coal tar wash oil. This method fully extracts crystalline substances such as acenaphthene, fluorene, and fluorene, reduces the content of acenaphthene to below 1%, and the content of the three components to below 5%. It can reduce the crystallinity of the wash oil to below 0°C and increase the utilization rate of the wash oil by more than 30%.

[0006] CN102268273A discloses a continuous oil washing process, which can improve the purity of α-methylnaphthalene and β-methylnaphthalene to ≥95% and the purity of acenaphthene to ≥96%.

[0007] CN101899313A discloses an eight-furnace, eight-tower deep processing technology for washing oil, which can be used to obtain β-methylnaphthalene, α-methylnaphthalene, acenaphthene, fluorene and oxyfluorene products with a purity of ≥98%.

[0008] However, coal tar wash oil is a multiphase system, and the separation and purification of its chemicals is much more difficult than the fine separation of general chemical products. The main technical challenges are as follows:

[0009] (1) Wash oil fraction contains a large number of isomers, such as α-methylnaphthalene, β-methylnaphthalene, acenaphthene, fluorene, etc. Their molecular size and chemical properties are extremely similar. At the same time, there are multi-component azeotropic and multi-component high / low boiling point eutectic systems, which makes it almost impossible for distillation and crystallization separation technologies to achieve high-purity separation.

[0010] (2) Industrial distillation requires a high theoretical plate number, the separation system needs to operate at high temperature, and the energy consumption, cost and process are high. Polycyclic aromatic hydrocarbon products obtained by industrial recrystallization often have problems such as large solvent consumption, low yield and low purity.

[0011] (3) Wash oil fraction is a multiphase system with extremely complex composition, containing hundreds of compounds. Its thermodynamic, rheological, mass transfer and heat transfer characteristics are more complex than those of general chemical systems.

[0012] (4) Wash oil fraction contains a large amount of heat-sensitive substances such as α-methylnaphthalene, oxyfluorene, dimethylfluorene, and pentanol. During the repeated heating and cooling processes of distillation and crystallization, polymerization or cracking reactions are very likely to occur, which not only leads to a decrease in product yield, but also the cracking products are easy to form deposits and colloids, which become sticky residues that block the pipeline.

[0013] Existing separation methods, such as traditional distillation and crystallization techniques, have limitations in the high-purity separation of isomers, azeotropic and high / low boiling point eutectic systems, and cannot obtain high-purity products with a purity of ≥99%. Summary of the Invention

[0014] In view of the problems existing in the prior art, the purpose of the present invention is to provide a system device and method for extracting electronic-grade chemicals from coal tar wash oil fraction, so as to solve the defects of the prior art in the separation of isomers, azeotropic and high / low boiling point eutectic systems, which are poor in separation effect and cannot obtain electronic-grade products.

[0015] To achieve this objective, the present invention adopts the following technical solution:

[0016] In a first aspect, the present invention provides a system apparatus for extracting electronic-grade chemicals from coal tar wash oil fractions, the system apparatus comprising:

[0017] The unit includes a pretreatment unit, a mixed methylnaphthalene refining unit, a fluorene refining unit, and an acenaphthene refining unit.

[0018] The side-line material outlet of the pretreatment unit is connected to the feed inlet of the mixed methylnaphthalene refining unit;

[0019] The material outlet at the bottom of the pretreatment unit is connected to the feed inlet of the fluorene refining unit;

[0020] The bottom outlet of the fluorene refining unit is connected to the feed inlet of the acenaphthene refining unit.

[0021] The system provided by this invention, through the selection and design of equipment within the system, enables the extraction of electronic-grade chemicals from coal tar wash oil fractions. First, it effectively separates the isomers in the target component, followed by subsequent distillation separation and purification, thereby ultimately achieving the extraction of electronic-grade chemicals.

[0022] As a preferred embodiment of the present invention, the pretreatment unit includes a first distillation column.

[0023] Preferably, a washing unit is further provided between the pretreatment unit and the mixed methylnaphthalene refining unit.

[0024] Preferably, the washing unit includes a washing tower.

[0025] Preferably, the side outlet of the pretreatment unit is connected to the inlet of the washing unit.

[0026] As a preferred technical solution of the present invention, the mixed methylnaphthalene refining unit includes a separation tower, a second distillation tower, a first cryogenic crystallization device, a first adsorption separation device, an alkali neutralization reactor, a second cryogenic crystallization device, and a sulfonation hydrolysis device.

[0027] Preferably, the top material outlet of the separation tower is connected to the material inlet of the second distillation tower, and the top material outlet of the second distillation tower is sequentially connected to the first cryogenic crystallization device and the first adsorption separation device.

[0028] Preferably, the bottom material outlet of the separation tower is connected in sequence to the alkali neutralization reactor, the second cryogenic crystallization device, and the sulfonation hydrolysis device.

[0029] As a preferred technical solution of the present invention, the fluorene refining unit includes a fluorene concentration tower, a third distillation tower, a fourth distillation tower, a first solvent crystallization device, a second solvent crystallization device, and a second adsorption separation device.

[0030] Preferably, the top material outlet of the fluorene concentration column is connected to the material inlet of the third distillation column.

[0031] Preferably, the top material outlet of the third distillation column is connected to the first solvent crystallization device.

[0032] Preferably, the bottom material outlet of the third distillation column is connected to the material inlet of the fourth distillation column.

[0033] Preferably, the top material outlet of the fourth distillation column is sequentially connected to the second solvent crystallization device and the second adsorption separation device.

[0034] As a preferred technical solution of the present invention, the acenaphthene refining unit includes a fifth distillation column, a melting crystallization device, and a third adsorption separation device.

[0035] Preferably, the bottom material outlet of the fluorene concentration column is connected to the material inlet of the fifth distillation column.

[0036] Preferably, the top material outlet of the fifth distillation column is sequentially connected to the melting crystallization device and the third adsorption separation device.

[0037] As a preferred embodiment of the present invention, the top material outlet of the pretreatment unit is connected to an industrial naphthalene storage device.

[0038] The top material outlet of the pretreatment unit and the bottom material outlet of the second distillation column are both connected to the medium-quality wash oil storage equipment.

[0039] The bottom material outlets of both the fourth and fifth distillation columns are connected to the carbon black feedstock oil storage equipment.

[0040] In a second aspect, the present invention provides a method for extracting electronic-grade chemicals from coal tar wash oil fractions, the method being carried out using the system apparatus for extracting electronic-grade chemicals from coal tar wash oil fractions as described in the first aspect, comprising:

[0041] The coal tar wash oil fraction is subjected to a first rectification to obtain side stream feed material and bottom product;

[0042] The material collected from the side stream was washed and then naphthalene was separated to obtain α-methylnaphthalene fraction and β-methylnaphthalene fraction;

[0043] The obtained β-methylnaphthalene fraction was subjected to a second distillation, a first freeze crystallization, a first centrifugal separation, and a first adsorption separation to obtain electronic-grade β-methylnaphthalene product;

[0044] The obtained α-methylnaphthalene fraction was subjected to neutralization treatment, second freeze crystallization, second centrifugation and sulfonation hydrolysis to obtain electronic grade α-methylnaphthalene product;

[0045] The material extracted from the bottom of the tower is concentrated to obtain fluorene material at the top of the tower and acenaphthene material at the bottom of the tower;

[0046] The fluorene material at the top of the column is successively subjected to biphenyl removal, third distillation and fourth distillation to obtain fluorene material;

[0047] The fluorene material was subjected to extraction crystallization and a second adsorption separation to obtain electronic-grade fluorene products;

[0048] The acenaphthene material at the bottom of the tower is sequentially subjected to fifth distillation, melt crystallization, and third adsorption separation to obtain electronic-grade acenaphthene product.

[0049] As a preferred technical solution of the present invention, the coal tar wash oil fraction is a coal tar wash oil fraction with a temperature of 200-330℃.

[0050] Preferably, the final boiling point of the material extracted from the side stream is 240-270℃.

[0051] Preferably, the final boiling point of the material drawn from the bottom of the tower is 300-320℃.

[0052] As a preferred technical solution of the present invention, in the first distillation, the pressure at the top of the column is controlled at 10-500 kPa, the temperature at the top of the column is controlled at 100-200℃, the pressure at the bottom of the column is controlled at 10-300 kPa, the temperature at the bottom of the column is controlled at 130-330℃, and the reflux ratio is controlled at 1-15, so as to obtain α-methylnaphthalene fraction and β-methylnaphthalene fraction.

[0053] Preferably, in the naphthalene separation process, the pressure at the top of the column is controlled at 10-500 kPa, the temperature at the top of the column is controlled at 100-200°C, the pressure at the bottom of the column is controlled at 10-500 kPa, the temperature at the bottom of the column is controlled at 150-260°C, and the reflux ratio is controlled at 5-20.

[0054] Preferably, in the second distillation process, the top temperature of the column is controlled at 100-400℃, the top pressure at 10-500kPa, the bottom temperature at 50-350℃, the bottom pressure at 50-400kPa, and the reflux ratio at 5-20.

[0055] Preferably, the temperature during the first freeze-crystallization is -20°C to 40°C.

[0056] Preferably, the cooling rate during the first freeze crystallization is controlled at 0.1-10℃ / min.

[0057] Preferably, the adsorption time in the first adsorption separation is 15-180 min.

[0058] Preferably, the adsorption temperature of the first adsorption separation is 25-100℃.

[0059] Preferably, the neutralization is performed using an alkali, and the endpoint of the neutralization is when the pH value of the material is 6-10.

[0060] Preferably, the temperature of the second freeze crystallization is -50℃ to 30℃.

[0061] Preferably, the cooling rate in the second freeze crystallization is 0.1-10℃ / min.

[0062] Preferably, the reaction temperature of the sulfonation hydrolysis is 200-400℃.

[0063] As a preferred technical solution of the present invention, the concentration process controls the column top temperature to be 100-220℃, the column top pressure to be 20-200kPa, the column bottom temperature to be 80-320℃, the column bottom pressure to be 10-220kPa, and the reflux ratio to be 5-25.

[0064] Preferably, the debiphenyl is controlled by setting the top temperature of the column to 150-350℃, the top pressure of the column to 10-300kPa, the bottom temperature of the column to 150-400℃, the bottom pressure of the column to 10-500kPa, and the reflux ratio to 5-20.

[0065] Preferably, in the third distillation process, the top temperature of the column is controlled at 100-300℃, the top pressure at 50-350kPa, the bottom temperature at 120-400℃, the top pressure at 30-400kPa, and the reflux ratio at 6-25.

[0066] Preferably, in the fourth distillation process, the top temperature of the column is controlled at 80-320℃, the top pressure at 50-350kPa, the bottom temperature at 150-400℃, the bottom pressure at 30-420kPa, and the reflux ratio at 6-25.

[0067] Preferably, the extraction and crystallization temperature is 25-100℃.

[0068] Preferably, the solvent addition amount in the extraction crystallization is solvent:feed amount of (1-1.5):1.

[0069] Preferably, the adsorption time in the second adsorption separation is 15-150 min.

[0070] Preferably, the temperature in the second adsorption separation is 25-120℃.

[0071] Preferably, in the fifth distillation process, the top temperature of the column is controlled at 100-200℃, the top pressure at 10-300kPa, the bottom temperature at 100-320℃, the bottom pressure at 10-300kPa, and the reflux ratio at 5-25.

[0072] Preferably, the melting and crystallization temperature is 25-230°C.

[0073] Preferably, the adsorption time in the third adsorption separation is 15-150 min.

[0074] Preferably, the temperature in the third adsorption separation is 25-200℃.

[0075] Compared with existing technical solutions, the present invention has the following beneficial effects:

[0076] (1) Adsorption separation technology is used to couple isomer systems, multi-component azeotropic and multi-component high / low boiling point eutectic systems in complex multiphase systems such as wash oil fraction, which solves the problem of high-purity separation of special systems in wash oil that cannot be achieved by existing "distillation + crystallization" technology.

[0077] (2) Quinoline, thiophene, indole, etc. in the wash oil form azeotropes with target products such as acenaphthene, oxyfluorene, and fluorene. Quinoline acid is a viscous substance, which is very easy to clog the tower during the separation process. The quinoline content will have an important impact on the high-purity separation of subsequent products. Therefore, the pretreatment effect will be a key factor affecting the quality of subsequent products. The existing wash oil pretreatment process is: dehydration and slag removal - acid and alkali washing - naphthalene removal - distillation. This process produces a large amount of sodium phenolate and the quinoline removal rate is low. However, the present invention adopts the process of "naphthalene removal - crude separation - washing". After effective initial separation of isomers in the target component, acid washing is performed on the target fraction to remove quinoline. This process can not only achieve efficient removal of quinoline substances, but also greatly reduce the amount of acid used and the amount of sodium phenolate emitted. It has the characteristics of high quinoline removal rate, low pollutant emission, and high economy. (3) It can achieve efficient, accurate and reliable separation and purification to improve the stability and controllability of the process.

[0078] (4) By utilizing the overall process optimization technology, the theoretical plate number of industrial distillation can be reduced, and the impact of high-temperature operation of the separation system on energy consumption and cost can be reduced, thereby improving the economy and feasibility of the process.

[0079] (5) To address the problems of reduced product yield, decreased product purity, and formation of sediments and colloids caused by polymerization or cracking reactions during repeated heating and cooling processes in the existing distillation separation methods for heat-sensitive substances such as α-methylnaphthalene, oxyfluorene, dimethylfluorene, and pentanol contained in the wash oil fraction.

[0080] (6) By coupling multiple separation and purification technologies such as "distillation separation + extraction / crystallization purification + adsorption high-purity separation", the purpose of extracting electronic-grade products from wash oil can be achieved. Attached Figure Description

[0081] Figure 1 This is a schematic diagram of a system apparatus for extracting electronic-grade chemicals from coal tar wash oil fractions provided in an embodiment of the present invention;

[0082] Figure 2 This is a schematic diagram showing the dimensions of acenaphthene in the coal tar wash oil fraction in an embodiment of the present invention;

[0083] Figure 3 This is a schematic diagram showing the dimensions of fluorene in the coal tar wash oil fraction in an embodiment of the present invention;

[0084] Figure 4This is a schematic diagram showing the dimensions of the α-methylnaphthalene isomer, a fraction of coal tar wash oil, in an embodiment of the present invention.

[0085] Figure 5 This is a schematic diagram showing the dimensions of the isomer β-methylnaphthalene in the coal tar wash oil fraction of this invention.

[0086] In the diagram: 1.1 - First distillation column, 1.2 - Washing column, 2.1 - Separation column, 2.2.1 - Second distillation column, 2.2.2 - First cryogenic crystallization unit, 2.2.3 - First adsorption separation unit, 2.3.1 - Alkali neutralization reactor, 2.3.2 - Second cryogenic crystallization unit, 2.3.3 - Sulfonation hydrolysis unit, 3.1 - Fluorene concentration column, 3.2 - Bisphenyl removal column, 3.3.1 - Third distillation column, 3.3.2 - First solvent crystallization unit, 3.4.1 - Fourth distillation column, 3.4.2 - Second solvent crystallization unit, 3.4.3 - Second adsorption separation unit, 3.5.1 - Fifth distillation column, 3.5.2 - Melt crystallization unit, 3.5.3 - Third adsorption separation unit;

[0087] A - Industrial naphthalene, B - Electronic grade β-methylnaphthalene product, C - Electronic grade α-methylnaphthalene product, D - Medium-quality wash oil, E - Crude biphenyl, F - Industrial fluorene oxide product, G - Electronic grade fluorene product, H - Carbon black feedstock oil, J - Electronic grade acenaphthene product.

[0088] The present invention will now be described in further detail. However, the examples described below are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the claims. Detailed Implementation

[0089] To better illustrate the present invention and facilitate understanding of its technical solutions, typical but non-limiting embodiments of the present invention are as follows:

[0090] This embodiment provides a system apparatus for extracting electronic-grade chemicals from coal tar wash oil fractions, such as... Figure 1 As shown, it includes: a pretreatment unit, a mixed methylnaphthalene refining unit, a fluorene refining unit, and an acenaphthene refining unit;

[0091] The side-line material outlet of the pretreatment unit is connected to the feed inlet of the mixed methylnaphthalene refining unit;

[0092] The material outlet at the bottom of the pretreatment unit is connected to the feed inlet of the fluorene refining unit;

[0093] The bottom outlet of the fluorene refining unit is connected to the feed inlet of the acenaphthene refining unit.

[0094] The pretreatment unit includes a first distillation column 1.1;

[0095] A washing unit is also provided between the pretreatment unit and the mixed methylnaphthalene refining unit;

[0096] The washing unit includes a washing tower 1.2;

[0097] The material outlet of the pretreatment unit is connected to the feed inlet of the washing unit.

[0098] In this invention, the coal tar wash oil fraction is fed into the feed port in the middle of the first distillation column 1.1 in the pretreatment unit.

[0099] In this invention, after the first distillation column 1.1 is operated, the industrial naphthalene A is collected from the top of the column for commercial sale or for use in other processes.

[0100] The mixed methylnaphthalene refining unit includes a separation tower 2.1, a second distillation tower 2.2.1, a first cryogenic crystallization device 2.2.2, a first adsorption separation device 2.2.3, an alkali neutralization reactor 2.3.1, a second cryogenic crystallization device 2.3.2, and a sulfonation hydrolysis device 2.3.3.

[0101] The top material outlet of the separation tower 2.1 is connected to the material inlet of the second distillation tower 2.2.1, and the top material outlet of the second distillation tower 2.2.1 is sequentially connected to the first cryogenic crystallization device 2.2.2 and the first adsorption separation device 2.2.3;

[0102] In this invention, electronic-grade β-methylnaphthalene product B is obtained after processing by the first adsorption separation device 2.2.3.

[0103] The bottom material outlet of the separation tower 2.1 is connected in sequence to the alkali neutralization reactor 2.3.1, the second cryogenic crystallization device 2.3.2, and the sulfonation hydrolysis device 2.3.3.

[0104] In this invention, the product obtained after treatment by the sulfonation hydrolysis equipment 2.3.3 is electronic grade α-methylnaphthalene product C.

[0105] In this invention, the material obtained from the washing unit is fed into the middle of the separation column 2.1 through the material inlet. The material inlet of the second distillation column 2.2.1 is located in the middle of the column.

[0106] The fluorene refining unit includes a fluorene concentration tower 3.1, a third distillation tower 3.3.1, a fourth distillation tower 3.4.1, a first solvent crystallization device 3.3.2, a second solvent crystallization device 3.4.2, and a second adsorption separation device 3.4.3.

[0107] In this invention, the feed inlets of the fluorene concentration tower 3.1, the third distillation tower 3.3.1, and the fourth distillation tower 3.4.1 are all located in the middle of the tower.

[0108] The top material outlet of the fluorene concentration column 3.1 is connected to the material inlet of the third distillation column 3.3.1; the top material outlet of the third distillation column 3.3.1 is connected to the first solvent crystallization device 3.3.2; the bottom material outlet of the third distillation column 3.3.1 is connected to the material inlet of the fourth distillation column 3.4.1; the top material outlet of the fourth distillation column 3.4.1 is sequentially connected to the second solvent crystallization device 3.4.2 and the second adsorption separation device 3.4.3.

[0109] Furthermore, a biphenyl removal tower 3.2 is also provided between the fluorene concentration tower 3.1 and the third distillation tower 3.3.1, and the bottom material outlet of the biphenyl removal tower 3.2 is connected to the material inlet of the third distillation tower 3.3.1. The material is fed into the tower 3.2 through its central inlet.

[0110] In this invention, crude biphenyl E is produced at the top of the biphenyl removal tower 3.2.

[0111] In this invention, the product obtained after processing by the first solvent crystallization device 3.3.2 is industrial fluorene product F.

[0112] In this invention, the product obtained after processing by the second adsorption separation device 3.4.3 is electronic-grade fluorene product G.

[0113] The acenaphthene refining unit includes a fifth distillation column 3.5.1, a melt crystallization device 3.5.2, and a third adsorption separation device 3.5.3.

[0114] In this invention, the material inlet of the fifth distillation column 3.5.1 is located in the middle of the column.

[0115] The bottom material outlet of the fluorene concentration tower 3.1 is connected to the material inlet of the fifth distillation tower 3.5.1; the top material outlet of the fifth distillation tower 3.5.1 is connected in sequence to the melting crystallization device 3.5.2 and the third adsorption separation device 3.5.3.

[0116] In this invention, the product obtained after processing by the third adsorption separation device 3.5.3 is electronic-grade acenaphthene product J.

[0117] Furthermore, the top material outlet of the pretreatment unit is connected to an industrial naphthalene storage device;

[0118] The material outlet of the pretreatment unit and the bottom material outlet of the second distillation column 2.2.1 are both connected to the medium wash oil storage equipment; the obtained medium wash oil D can be sold directly as a benzene washing agent or used in the next stage.

[0119] The bottom material outlets of the fourth distillation column 3.4.1 and the fifth distillation column 3.5.1 are both connected to the carbon black feed oil storage equipment. The bottom materials of the fourth distillation column 3.4.1 and the fifth distillation column 3.5.1 are produced as carbon black feed oil H, which can be sold as raw material for carbon black production or directly transported to the next stage via pipeline.

[0120] To further clarify the preparation process of the aforementioned system device, a method for extracting electronic-grade chemicals from coal tar wash oil fraction is provided below, specifically including:

[0121] The coal tar wash oil fraction is subjected to a first rectification to obtain side stream feed material and bottom product;

[0122] The material collected from the side stream was washed and then naphthalene was separated to obtain α-methylnaphthalene fraction and β-methylnaphthalene fraction;

[0123] The obtained β-methylnaphthalene fraction was subjected to a second distillation, a first freeze crystallization, a first centrifugal separation, and a first adsorption separation to obtain electronic-grade β-methylnaphthalene product;

[0124] The obtained α-methylnaphthalene fraction was subjected to neutralization treatment, second freeze crystallization, second centrifugation and sulfonation hydrolysis to obtain electronic grade α-methylnaphthalene product;

[0125] The material extracted from the bottom of the tower is concentrated to obtain fluorene material at the top of the tower and acenaphthene material at the bottom of the tower;

[0126] The fluorene material at the top of the column is subjected to biphenyl removal, third distillation, and fourth distillation to obtain fluorene material;

[0127] The fluorene material was subjected to extraction crystallization and a second adsorption separation to obtain electronic-grade fluorene products;

[0128] The acenaphthene material at the bottom of the tower is sequentially subjected to fifth distillation, melt crystallization and third adsorption separation to obtain electronic-grade acenaphthene product;

[0129] Specifically, the coal tar wash oil fraction is a coal tar wash oil fraction at 200-330℃.

[0130] Specifically, the final boiling point of the material extracted from the side stream is 240-270℃, for example, it can be 240℃, 245℃, 250℃, 252℃, 254℃, 256℃, 258℃, 260℃, 265℃ or 270℃, etc., but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0131] In this invention, the side-stream extracted material includes a denaphthalene fraction and a middle fraction, wherein the final boiling point of the denaphthalene fraction is 240-260℃ and the final boiling point of the middle fraction is 260-270℃.

[0132] In this invention, the final boiling point of the denaphthalene fraction is 240-260℃, for example, it can be 240℃, 245℃, 250℃, 255℃ or 260℃, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0133] In this invention, the final boiling point of the middle fraction is 260-270℃, for example, it can be 260℃, 265℃, 270℃, 275℃ or 280℃, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0134] Specifically, the final boiling point of the material drawn from the bottom of the tower is 300-320℃, for example, it can be 300℃, 305℃, 310℃, 315℃ or 320℃, etc., but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0135] Specifically, the washing includes acid washing and alkali washing. The washing process includes: firstly, acid washing is performed to remove pyridine and quinoline, and then the acid-washed oil sample is neutralized with alkali solution.

[0136] The pickling process involves using pickling solutions such as sulfuric acid and carbonic acid to clean the material at a temperature of 25-80℃ for 15-60 minutes, with the mass ratio of pickling agent to material being 1:(1-8).

[0137] The alkaline washing involves using alkaline washing agents such as sodium hydroxide and potassium hydroxide to clean for 10-80 minutes at a temperature of 25-80℃, with the mass ratio of alkaline washing agent to material being 1:(1-5).

[0138] Specifically, in the first distillation process, the pressure at the top of the column is controlled at 10-500 kPa, the temperature at the top of the column is controlled at 100-200℃, the pressure at the bottom of the column is controlled at 10-300 kPa, the temperature at the bottom of the column is controlled at 130-330℃, and the reflux ratio is controlled at 1-15, so as to obtain α-methylnaphthalene fraction and β-methylnaphthalene fraction.

[0139] The pressure at the top of the first distillation column is 10-500 kPa, for example, it can be 10 kPa, 50 kPa, 100 kPa, 200 kPa, 300 kPa, 400 kPa or 500 kPa, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0140] The temperature at the top of the first distillation column is 100-200℃, for example, it can be 100℃, 120℃, 140℃, 160℃, 180℃ or 200℃, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0141] The pressure in the reboiler of the first distillation column is 10-300 kPa, for example, it can be 10 kPa, 50 kPa, 100 kPa, 200 kPa or 300 kPa, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0142] The temperature of the reboiler in the first distillation column is 130-330℃, for example, it can be 130℃, 140℃, 160℃, 180℃, 200℃, 220℃, 230℃, 250℃, 260℃, 280℃, 300℃ or 330℃, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0143] Specifically, in the naphthalene separation process, the pressure at the top of the column is controlled at 10-500 kPa, the temperature at the top of the column is controlled at 100-200℃, the pressure at the bottom of the column is controlled at 10-500 kPa, the temperature at the bottom of the column is controlled at 150-260℃, and the reflux ratio is controlled at 5-20, so as to achieve efficient separation of α-methylnaphthalene and β-methylnaphthalene.

[0144] The pressure at the top of the control tower in the naphthalene separation process is 10-500 kPa, for example, it can be 10 kPa, 50 kPa, 100 kPa, 200 kPa, 300 kPa, 400 kPa or 500 kPa, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0145] The temperature at the top of the naphthalene separation column is controlled to be 100-200℃, for example, 100℃, 120℃, 140℃, 160℃, 180℃ or 200℃, but not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0146] The pressure of the control tower in the naphthalene separation process is 10-300 kPa, for example, it can be 10 kPa, 50 kPa, 100 kPa, 200 kPa, 300 kPa, etc., but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0147] The temperature of the naphthalene separation tower is controlled at 150-260℃, for example, it can be 150℃, 180℃, 200℃, 240℃, 240℃, 260℃, etc., but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0148] The reflux ratio in the naphthalene separation is 5-20, for example, it can be 5, 10, 15 or 20, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0149] Specifically, the second distillation is an azeotropic distillation, in which the top temperature of the column is controlled at 100-400℃, the top pressure at 10-500kPa, the bottom temperature at 50-350℃, the bottom pressure at 50-400kPa, and the reflux ratio at 5-20.

[0150] In the second distillation process, the top temperature of the column is 100-400℃, for example, it can be 100℃, 150℃, 200℃, 250℃, 300℃, 350℃ or 400℃, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0151] The pressure at the top of the column in the second distillation process is 10-500 kPa, for example, it can be 10 kPa, 50 kPa, 100 kPa, 200 kPa, 300 kPa, 400 kPa or 500 kPa, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0152] The temperature of the reboiler in the second distillation column is 50-350℃, for example, it can be 50℃, 100℃, 150℃, 200℃, 250℃ or 300℃, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0153] The pressure in the reboiler of the second distillation column is 50-400 kPa, for example, it can be 50 kPa, 100 kPa, 200 kPa, 300 kPa or 400 kPa, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0154] The reflux ratio in the second distillation is 5-20, for example, it can be 5, 10, 15 or 20, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0155] Specifically, the first freeze crystallization involves controlling the temperature to be between -20°C and 40°C and the cooling rate to be between 0.1°C and 10°C / min, in order to achieve the desired compound crystallization.

[0156] The temperature during the first freeze-crystallization is -20℃ to 40℃, for example, it can be -20℃, -10℃, 0℃, 10℃, 20℃, 30℃ or 40℃, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0157] The cooling rate during the first freeze crystallization is controlled to be 0.1-10℃ / min, for example, it can be 0.1℃ / min, 0.5℃ / min, 1℃ / min, 2℃ / min, 4℃ / min, 6℃ / min, 8℃ / min or 10℃ / min, etc., but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0158] In this invention, industrial β-methylnaphthalene with a purity ≥95% is obtained after the first centrifugal separation.

[0159] Specifically, the first adsorption separation involves controlling the adsorption time to 15-180 min and the adsorption temperature to be in the range of 25-100℃.

[0160] In this invention, the adsorbent used in the first adsorption is selected based on the properties of the larger molecular weight polycyclic aromatic hydrocarbon impurities in the wash oil, such as the commonly used adsorption molecular sieve in the art.

[0161] In this invention, the adsorption time in the first adsorption separation is 15-180 min, for example, it can be 15 min, 20 min, 40 min, 60 min, 80 min, 100 min, 120 min, 140 min, 160 min or 180 min, etc., but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0162] The adsorption temperature of the first adsorption separation is 25-100℃, for example, it can be 25℃, 30℃, 40℃, 50℃, 60℃, 70℃, 80℃, 90℃ or 100℃, etc., but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0163] In this invention, after the first adsorption separation is completed, an electronic-grade β-methylnaphthalene product with a purity of ≥99.9% is obtained.

[0164] Specifically, the neutralization is performed using an alkali, and the endpoint of the neutralization is when the pH value of the material is between 6 and 10. For example, it can be 6, 7, 8, 9 or 10, but it is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0165] Specifically, the temperature in the second freeze crystallization is controlled at -50℃ to 30℃, and the cooling rate is 0.1-10℃ / min.

[0166] The temperature of the second freeze crystallization is -50℃ to 30℃, for example, it can be -50℃, -40℃, -30℃, -20℃, -10℃, 0℃, 10℃, 20℃ or 30℃, etc., but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0167] The cooling rate in the second freeze crystallization is 0.1-10℃ / min, for example, it can be 0.1℃ / min, 0.5℃ / min, 1℃ / min, 2℃ / min, 4℃ / min, 6℃ / min, 8℃ / min or 10℃ / min, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0168] In this invention, the second centrifugal separation yields industrial α-methylnaphthalene with a purity ≥95%.

[0169] Specifically, the sulfonation hydrolysis is performed at a controlled reaction temperature of 200-400℃, such as 200℃, 250℃, 300℃, 350℃ or 400℃, but not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0170] In this invention, sulfonation hydrolysis yields industrial α-methylnaphthalene, which undergoes a sulfonation reaction with sulfuric acid at 60-100°C. After the reaction is complete, the product is hydrolyzed and separated into layers in dilute sulfuric acid (20-40 wt%), followed by washing with a 5-15% NaOH solution and water to obtain the final product.

[0171] In this invention, an electronic-grade α-methylnaphthalene product with a purity of ≥99.9% is obtained after sulfonation and hydrolysis.

[0172] Specifically, in the concentration process, the top temperature of the column is controlled at 100-220℃, the top pressure at 20-200kPa, the bottom temperature at 80-320℃, the bottom pressure at 10-220kPa, and the reflux ratio at 5-25.

[0173] The concentration process involves a tower top temperature of 100-220℃, which can be, for example, 100℃, 120℃, 140℃, 160℃, 180℃, 200℃ or 220℃, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0174] The pressure at the top of the column during the concentration process is 20-200 kPa, for example, it can be 20 kPa, 50 kPa, 100 kPa, 150 kPa or 200 kPa, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0175] The temperature of the distillation column in the concentration process is 80-320℃, for example, it can be 80℃, 100℃, 150℃, 200℃, 250℃, 300℃ or 320℃, etc., but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0176] The pressure in the distillation column during the concentration process is 10-220 kPa, for example, it can be 10 kPa, 50 kPa, 100 kPa, 150 kPa, 200 kPa or 220 kPa, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0177] The reflux ratio in the concentration process is 5-25, for example, it can be 5, 10, 15, 20 or 25, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0178] Specifically, the debiphenyl is controlled by setting the top temperature of the column to 150-350℃, the top pressure of the column to 10-300kPa, the bottom temperature of the column to 150-400℃, the bottom pressure of the column to 10-500kPa, and the reflux ratio to 5-20.

[0179] The temperature at the top of the debiphenyl tower is 150-400℃, for example, it can be 150℃, 200℃, 250℃, 300℃ or 350℃, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0180] The pressure at the top of the debiphenyl tower is 10-300 kPa, for example, it can be 10 kPa, 50 kPa, 100 kPa, 200 kPa or 300 kPa, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0181] In this invention, the temperature of the reboiler in the biphenyl removal tower is 150-400℃, for example, it can be 150℃, 200℃, 250℃, 300℃ or 350℃, etc., but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0182] In this invention, the pressure in the distillation tower of the biphenyl debenzene is 10-500 kPa, for example, it can be 10 kPa, 50 kPa, 100 kPa, 200 kPa, 300 kPa, 400 kPa or 500 kPa, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0183] In this invention, the reflux ratio in the debiphenyl is 5-20, for example, it can be 5, 8, 10, 15, 18 or 20, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0184] Specifically, in the third distillation process, the top temperature of the column is controlled at 100-300℃, the top pressure at 50-350kPa, the bottom temperature at 120-400℃, the top pressure at 30-400kPa, and the reflux ratio at 6-25, so as to obtain fluorene material at the top of the column and acenaphthene material at the bottom of the column.

[0185] The top temperature of the third distillation column is 100-300℃, for example, it can be 100℃, 150℃, 200℃, 250℃ or 300℃, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0186] The pressure at the top of the third distillation column is 50-350 kPa, for example, it can be 50 kPa, 100 kPa, 110 kPa, 120 kPa, 130 kPa, 140 kPa, 150 kPa, 200 kPa, 250 kPa, 300 kPa or 350 kPa, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0187] The temperature of the reboiler in the third distillation column is 120-400℃, for example, it can be 120℃, 200℃, 250℃, 300℃, 350℃ or 400℃, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0188] The pressure at the top of the third distillation column is 30-400 kPa, for example, it can be 30 kPa, 100 kPa, 200 kPa, 300 kPa or 400 kPa, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0189] The reflux ratio in the third distillation is 6-25, for example, it can be 6, 10, 15, 20 or 25, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0190] Specifically, in the fourth distillation process, the top temperature of the column is controlled at 80-320℃, the top pressure at 50-350kPa, the bottom temperature at 150-400℃, the bottom pressure at 30-420kPa, and the reflux ratio at 6-25.

[0191] The temperature at the top of the column in the fourth distillation process is controlled to be 80-320℃, for example, it can be 80℃, 140℃, 180℃, 220℃, 260℃, 300℃, 320℃, etc., but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0192] The control column top pressure in the fourth distillation process is 50-350 kPa, for example, it can be 50 kPa, 100 kPa, 130 kPa, 150 kPa, 180 kPa, 200 kPa, 260 kPa, 290 kPa, 320 kPa, 350 kPa, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0193] The temperature of the reboiler in the fourth distillation column is 150-400℃, for example, it can be 150℃, 200℃, 250℃, 300℃, 350℃ or 400℃, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0194] The pressure in the reboiler of the fourth distillation column is 30-420 kPa, for example, it can be 30 kPa, 50 kPa, 100 kPa, 200 kPa, 300 kPa, 400 kPa or 420 kPa, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0195] The reflux ratio in the fourth distillation is 6-25, for example, it can be 6, 8, 10, 15, 18, 20 or 25, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0196] In this invention, industrial fluorene with a purity of ≥96% is obtained after the fourth distillation.

[0197] Specifically, the temperature during the extraction and crystallization process is controlled at 25-100℃, and the solvent addition ratio is (1-1.5):1 (solvent:feed).

[0198] The extraction and crystallization temperature is 25-100℃, for example, it can be 25℃, 30℃, 40℃, 50℃, 60℃, 70℃, 80℃, 90℃ or 100℃, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0199] The solvent addition during the extraction crystallization is in the form of solvent:feed ratio of (1-1.5):1, for example, it can be 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1 or 1.5:1, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0200] Specifically, the second adsorption separation involves controlling the adsorption time to be 15-150 min and the temperature to be 25-120℃.

[0201] In the second adsorption separation, the adsorption time is 15-150 min, for example, it can be 15 min, 20 min, 40 min, 60 min, 80 min, 100 min, 120 min, 140 min or 150 min, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0202] The temperature in the second adsorption separation is 25-120℃, for example, it can be 25℃, 30℃, 40℃, 50℃, 60℃, 70℃, 80℃, 90℃, 100℃, 110℃ or 120℃, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0203] In this invention, after the second adsorption separation, electronic-grade fluorene with a purity ≥99.9% is obtained.

[0204] Specifically, in the fifth distillation process, the top temperature of the column is controlled at 100-200℃, the top pressure at 10-300kPa, the bottom temperature at 100-320℃, the bottom pressure at 10-300kPa, and the reflux ratio at 5-25.

[0205] The top temperature of the fifth distillation column is 100-200℃, for example, it can be 100℃, 120℃, 140℃, 160℃, 180℃ or 200℃, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0206] The pressure at the top of the fifth distillation column is 10-300 kPa, for example, it can be 10 kPa, 50 kPa, 100 kPa, 200 kPa or 300 kPa, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0207] The temperature of the reboiler in the fifth distillation column is 100-320℃, for example, it can be 100℃, 120℃, 140℃, 160℃, 180℃, 200℃, 220℃, 240℃, 260℃, 280℃, 300℃ or 320℃, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0208] The pressure of the reboiler in the fifth distillation column is 10-300 kPa, for example, it can be 10 kPa, 50 kPa, 100 kPa, 200 kPa or 300 kPa, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0209] The reflux ratio of the fifth distillation is 5-25, for example, it can be 5, 14, 18, 20, 23, 25, etc., but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0210] Specifically, the melting and crystallization is carried out at a controlled temperature of 25-230℃, such as 25℃, 50℃, 100℃, 150℃, 200℃ or 230℃, etc., but not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0211] In this invention, the melt crystallization involves cooling the material from the top of the fifth distillation column to room temperature, then slowly heating it above its melting point to completely melt it into a liquid state; then slowly lowering the temperature to allow the target compound to gradually cool and crystallize out; and finally obtaining the product after filtration, centrifugation, washing and drying.

[0212] In this invention, the acenaphthene product with a purity ≥98% is obtained after the melt crystallization treatment.

[0213] Specifically, the third adsorption separation involves controlling the adsorption time to be 15-150 min and the temperature to be 25-200℃.

[0214] The adsorption time in the third adsorption separation is 15-150 min, for example, it can be 15 min, 20 min, 40 min, 60 min, 80 min, 100 min, 120 min, 140 min or 150 min, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0215] The temperature in the third adsorption separation is 25-200℃, for example, it can be 25℃, 50℃, 100℃, 150℃, or 200℃, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0216] In this invention, the third adsorption separation yields electronic-grade acenaphthene with a purity ≥ 99.9%.

[0217] To further illustrate the superior performance of the system device provided by the present invention, the present invention specifically provides the following usage embodiments to demonstrate the advantages of the solution provided by the present invention:

[0218] The properties of the wash oil fractions used in the following examples and comparative examples are shown in Table 1. The molecular size of acenaphthene in the wash oil fractions is as follows: Figure 2 As shown, the molecular size of fluorene in the wash oil fraction is as follows: Figure 3 As shown, the molecular size of the isomer α-methylnaphthalene in the wash oil fraction is as follows: Figure 4 As shown, the molecular size of the isomer β-methylnaphthalene in the wash oil fraction is as follows: Figure 5 As shown.

[0219] Table 1

[0220] Main products in wash oil Naphthalene Quinoline β-Methylnaphthalene α-Methylnaphthalene Biphenyl Acenaphthene Dibenzofuran Fluorene Mass percentage / % 5.58 1.62 13.6 5.4 3.22 20.83 13.08 14.05

[0221] Example 1

[0222] This embodiment provides a coupled processing technology for separating and extracting electronic-grade chemicals from coal tar wash oil fractions. The specific steps are as follows:

[0223] (a) The wash oil fraction of high-temperature coal tar at 200-330℃ is fed into a denaphthalene removal tower for the first rectification. The naphthalene oil fraction is collected at the top of the denaphthalene removal tower, the denaphthalene fraction and the middle fraction are collected from the side stream, and the heavy fraction is collected from the bottom of the tower. The final boiling point of the naphthalene oil fraction is 220℃, the final boiling point of the denaphthalene fraction is 250℃, the final boiling point of the middle fraction is 260℃, and the final boiling point of the heavy fraction is 320℃.

[0224] (b) The naphthalene oil fraction obtained in step (a) can be sold directly as crude naphthalene product, and the medium-quality wash oil can be sold directly as a benzene washing agent.

[0225] (c) The naphthalene-free wash oil obtained in step (a) is fed into a pretreatment tower for washing to remove quinoline by acid washing and pyridine by alkali washing to obtain quinoline-free wash oil;

[0226] (d) The dequinoline wash oil obtained in step (c) is fed into a mixed methylnaphthalene separation tower for naphthalene separation. The β-methylnaphthalene fraction is obtained from the top of the mixed methylnaphthalene separation tower, and the α-methylnaphthalene fraction is obtained from the bottom of the tower.

[0227] Each fraction then enters the high-purity separation section:

[0228] ①The β-methylnaphthalene fraction obtained in step (d) is subjected to a second distillation, a first freeze crystallization, and a first centrifugal separation to obtain industrial β-methylnaphthalene;

[0229] ②The industrial β-methylnaphthalene obtained in step ① is subjected to first adsorption separation by chromatography to obtain electronic grade β-methylnaphthalene product;

[0230] ③ The α-methylnaphthalene fraction obtained in step (d) is neutralized, and then subjected to a second freeze crystallization and a second centrifugation to obtain industrial α-methylnaphthalene;

[0231] ④ The industrial α-methylnaphthalene obtained in step ③ is subjected to sulfonation and hydrolysis to finally obtain electronic-grade α-methylnaphthalene product;

[0232] (e) The heavy fraction obtained in step (a) is fed into a fluorene enrichment column for enrichment treatment. The crude fluorene fraction obtained at the top of the column is fed into the fluorene refining unit; the crude acenaphthene obtained at the bottom of the column is fed into the acenaphthene refining unit.

[0233] (f) The crude fluorene fraction obtained in step (e) is subjected to biphenyl removal, third distillation and fourth distillation to obtain industrial fluorene. The industrial fluorene is then subjected to solvent extraction crystallization and second adsorption separation to finally obtain electronic grade fluorene. The heavy oil in the bottom of the fluorene tower is used as the raw material for crude oxygen fluorene refining and enters the oxygen fluorene refining unit.

[0234] (g) The crude acenaphthene fraction obtained in step (f) is subjected to a fifth distillation, and industrial acenaphthene is obtained at the top of the column;

[0235] (h) The industrial acenaphthene obtained in step (h) is melted and crystallized in a melting crystallizer to obtain refined acenaphthene product;

[0236] (i) The refined acenaphthene obtained in step (i) enters the chromatographic separator and undergoes the third adsorption separation to finally obtain high-purity acenaphthene;

[0237] (j) The crude oxygen fluorene obtained in step (g) is purified in a crude oxygen fluorene tower, and the industrial oxygen fluorene product is obtained at the top of the tower.

[0238] (k) The residual oil obtained from the bottom of the column in steps (h) and (k) is sold as a raw material for the production of carbon black.

[0239] The specific control parameters and index results in the embodiments are detailed in Table 2 below.

[0240] Table 2

[0241]

[0242]

[0243] Example 2

[0244] The only difference from Example 1 is that the operation process remains the same; the operation parameters and index results are detailed in Table 3.

[0245] Table 3

[0246]

[0247]

[0248] Example 3

[0249] The only difference from Example 1 is that the operation process remains the same, but the operation parameters are changed to Table 4.

[0250] Table 4

[0251]

[0252] Comparative Example 1

[0253] The only difference from Example 1 is that no neutralization treatment is performed.

[0254] Comparative Example 2

[0255] The only difference from Example 1 is that sulfonation hydrolysis is not performed.

[0256] Comparative Example 3

[0257] The only difference from Example 1 is that the debiphenyl process is not performed.

[0258] Comparative Example 4

[0259] The only difference from Example 1 is that melt crystallization is not performed.

[0260] Comparative Example 5

[0261] The only difference from Example 1 is that the first adsorption separation, the second adsorption separation, and the third adsorption separation are not performed.

[0262] All the above towers were operated under negative pressure. The main product information for the examples and comparative examples is shown in Table 5.

[0263] Table 5

[0264]

[0265] In this invention, wt% refers to the percentage content by mass.

[0266] As can be seen from the results of the above embodiments, the system device provided by the present invention, through the selection and design of the equipment within the system, realizes the extraction of electronic-grade chemicals from coal tar wash oil fractions. First, it effectively separates the isomers in the target component, and then performs subsequent distillation separation and purification, thereby finally realizing the extraction of electronic-grade chemicals.

[0267] The present invention is described in detail through the above embodiments, but the present invention is not limited to the above detailed structural features, that is, it does not mean that the present invention must rely on the above detailed structural features to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions for the components used in the present invention, additions of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

[0268] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0269] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0270] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A system for extracting electronic-grade chemicals from coal tar wash oil fractions, characterized in that, The system for extracting electronic-grade chemicals from coal tar wash oil fractions includes: The unit includes a pretreatment unit, a mixed methylnaphthalene refining unit, a fluorene refining unit, and an acenaphthene refining unit. The pretreatment unit includes a first distillation column for removing industrial naphthalene; A washing unit is provided between the pretreatment unit and the mixed methylnaphthalene refining unit for removing quinoline; The side-line material outlet of the pretreatment unit is connected to the mixed methylnaphthalene refining unit via the washing unit; The mixed methylnaphthalene refining unit includes a separation tower, a second distillation tower, a first cryogenic crystallization device, a first adsorption separation device, an alkali neutralization reactor, a second cryogenic crystallization device, and a sulfonation hydrolysis device. The top material outlet of the separation tower is connected to the material inlet of the second distillation tower, and the top material outlet of the second distillation tower is sequentially connected to the first cryogenic crystallization device and the first adsorption separation device to obtain electronic-grade β-methylnaphthalene product. The bottom material outlet of the separation tower is sequentially connected to the alkali neutralization reactor, the second cryogenic crystallization device, and the sulfonation hydrolysis device to obtain electronic-grade α-methylnaphthalene product. The material outlet at the bottom of the pretreatment unit is connected to the feed inlet of the fluorene refining unit; The material outlet at the bottom of the fluorene refining unit is connected to the feed inlet of the acenaphthene refining unit. The fluorene refining unit includes a fluorene concentration column, a third distillation column, a fourth distillation column, a first solvent crystallization device, a second solvent crystallization device, and a second adsorption separation device; a biphenyl removal column is also provided between the fluorene concentration column and the third distillation column; The top material outlet of the fluorene concentration column is connected to the material inlet of the biphenyl removal column; the bottom material outlet of the biphenyl removal column is connected to the material inlet of the third distillation column; the top material outlet of the third distillation column is connected to the first solvent crystallization device; the bottom material outlet of the third distillation column is connected to the material inlet of the fourth distillation column; and the top material outlet of the fourth distillation column is sequentially connected to the second solvent crystallization device and the second adsorption separation device. The acenaphthene refining unit includes a fifth distillation column, a melting crystallization device, and a third adsorption separation device; the bottom material outlet of the fluorene concentration column is connected to the material inlet of the fifth distillation column; the top material outlet of the fifth distillation column is sequentially connected to the melting crystallization device and the third adsorption separation device.

2. The system for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 1, characterized in that, The washing unit includes a washing tower.

3. The system for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 1, characterized in that, The top material outlet of the pretreatment unit is connected to an industrial naphthalene storage device; The top material outlet of the pretreatment unit and the bottom material outlet of the second distillation column are both connected to the medium-quality wash oil storage equipment. The bottom material outlets of both the fourth and fifth distillation columns are connected to the carbon black feedstock oil storage equipment.

4. A method for extracting electronic-grade chemicals from coal tar wash oil fractions, characterized in that, The method employs the system described in claim 1 for extracting electronic-grade chemicals from coal tar wash oil fractions, comprising: The coal tar wash oil fraction is fed into the pretreatment unit for the first distillation to obtain the side stream product and the bottom product. The material extracted from the side stream is fed into the washing unit for washing and then methylnaphthalene separation to obtain α-methylnaphthalene fraction and β-methylnaphthalene fraction; The obtained β-methylnaphthalene fraction was subjected to a second distillation, a first freeze crystallization, a first centrifugal separation, and a first adsorption separation to obtain electronic-grade β-methylnaphthalene product; The obtained α-methylnaphthalene fraction was subjected to neutralization treatment, second freeze crystallization, second centrifugation and sulfonation hydrolysis to obtain electronic grade α-methylnaphthalene product; The material collected from the bottom of the tower is fed into a fluorene concentration tower for concentration treatment to obtain fluorene material at the top of the tower and acenaphthene material at the bottom of the tower; The fluorene material at the top of the column is successively subjected to biphenyl removal, third distillation and fourth distillation to obtain fluorene material; The fluorene material was sequentially subjected to extraction crystallization and a second adsorption separation to obtain electronic-grade fluorene products; The acenaphthene material at the bottom of the tower is sequentially subjected to fifth distillation, melt crystallization, and third adsorption separation to obtain electronic-grade acenaphthene product.

5. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, The coal tar wash oil fraction is a coal tar wash oil fraction with a temperature of 200-330℃.

6. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, The final boiling point of the material extracted from the side stream is 240-270℃.

7. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, The final boiling point of the material extracted from the bottom of the tower is 300-320℃.

8. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, In the first distillation process, the pressure at the top of the column is controlled at 10-500 kPa, the temperature at the top of the column is controlled at 100-200℃, the pressure at the bottom of the column is controlled at 10-300 kPa, the temperature at the bottom of the column is controlled at 130-330℃, and the reflux ratio is controlled at 1-15, so as to obtain α-methylnaphthalene fraction and β-methylnaphthalene fraction.

9. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, In the methylnaphthalene separation process, the pressure at the top of the column is controlled at 10-500 kPa, the temperature at the top of the column is controlled at 100-200℃, the pressure at the bottom of the column is controlled at 10-500 kPa, the temperature at the bottom of the column is controlled at 150-260℃, and the reflux ratio is controlled at 5-20.

10. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, In the second distillation process, the top temperature of the column is controlled at 100-400℃, the top pressure at 10-500kPa, the bottom temperature at 50-350℃, the bottom pressure at 50-400kPa, and the reflux ratio at 5-20.

11. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, The temperature during the first freeze-crystallization was -20℃ to 40℃.

12. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, The cooling rate during the first freeze-crystallization is controlled at 0.1-10℃ / min.

13. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, The adsorption time in the first adsorption separation is 15-180 min.

14. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, The adsorption temperature of the first adsorption separation is 25-100℃.

15. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, The neutralization is performed using an alkali, and the endpoint of the neutralization is when the pH value of the material is 6-10.

16. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, The temperature for the second freeze crystallization is -50℃ to 30℃.

17. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, The cooling rate in the second freeze crystallization is 0.1-10℃ / min.

18. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, The reaction temperature for the sulfonation hydrolysis is 200-400℃.

19. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, In the concentration process, the top temperature of the column is controlled at 100-220℃, the top pressure at 20-200kPa, the bottom temperature at 80-320℃, the bottom pressure at 10-220kPa, and the reflux ratio at 5-25.

20. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, The debiphenyl control is achieved by maintaining a column top temperature of 150-350℃, a column top pressure of 10-300kPa, a column bottom temperature of 150-400℃, a column bottom pressure of 10-500kPa, and a reflux ratio of 5-20.

21. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, In the third distillation process, the top temperature of the column is controlled at 100-300℃, the top pressure at 50-350kPa, the bottom temperature at 120-400℃, and the reflux ratio at 6-25.

22. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, In the fourth distillation process, the top temperature of the column is controlled at 80-320℃, the top pressure at 50-350kPa, the bottom temperature at 150-400℃, the bottom pressure at 30-420kPa, and the reflux ratio at 6-25.

23. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, The extraction and crystallization temperature is 25-100℃.

24. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, The solvent addition amount in the extraction crystallization is solvent:feed amount of (1-1.5):

1.

25. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, The adsorption time in the second adsorption separation is 15-150 min.

26. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, The temperature in the second adsorption separation is 25-120℃.

27. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, In the fifth distillation process, the top temperature of the column is controlled at 100-200℃, the top pressure at 10-300kPa, the bottom temperature at 100-320℃, the bottom pressure at 10-300kPa, and the reflux ratio at 5-25.

28. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, The melting and crystallization temperature is 25-230℃.

29. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, The adsorption time in the third adsorption separation is 15-150 min.

30. The method for extracting electronic-grade chemicals from coal tar wash oil fraction as described in claim 4, characterized in that, The temperature in the third adsorption separation is 25-200℃.

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